End Cap Leak - Options?

[markpj23]

Hi - new member here. I have a cheap Chinese copy of a Highfield or GRant RIB with the fiberglass end cap steps. One of the end caps has filled with water as I can hear it sloshing around as I shake it. The seams appear to be alright but water is obviously getting in somewhere.


I am considering adding a drain - actually a 3/8" bait well plug - to the vertical surface of the end cap as a temporary measure until I can get the seams re-sealed. By this I mean the small crescent shaped area beneath the step - it angles slightly forward from vertical.


Wondering if anyone here has dealt with a similar issue? What other options do I have?


Thanks in advance,
Mark

[Peter_C]

Welcome to the forum

As there should be air pressure in the tube while boating there is no way for water to get into the air holding portion of the end cap or the air would quickly leak out. Therefore there must be a double wall of some sort. Try to listen to exactly where the water is holding and how much water it is holding. Search for a cracked seam most likely below water level. If you can find the break then it can be repaired after opening it up enough to drain it out.

I would tap it all over with a soft faced hammer and see if there are any funny sounds, like where the fiberglass or plastic is broken. Which begs the question what does the manufacturer use for the end cone material?

We need more information to help further.

[markpj23]

I can tell by tapping with my hands that the tube itself has nothing but air inside. It gives that 'hollow' sound up to the joint where the end cap is glued to it. The tube sounds the same on the port side where there is NO water in the end cap, so I'm pretty confident in this. The tubes have been inflated since I got the boat months ago and I'm sure that I would have seen a deflated tube by now if the water path into the end cap was through the air tube. Does that sound right?

I do see a seam where it has started to come apart - likely where the water gets forced in as the boat moves forward.


When I shake the end cap I can hear the water inside. I have no way to tell whether it's SMC or fiberglass.

Wondering if opening the seam is asking for more trouble than a hole through the end cap. But I guess either way I need to re-seal that seam. Tubes are supposed to be Hypalon - can you tell me which glue to buy?


Hoping to not make this worse than it is already....

[smallribber]

I would put a bung type device in the area you suggested low down to drain the water. The seal where it us getting in and job done

[Nasher]

Originally Posted by Peter_C

As there should be air pressure in the tube while boating there is no way for water to get into the air holding portion of the end cap or the air would quickly leak out.

Peter hi
Actually, that's not quite true from my experience.
Although I do realise it sounds impossible.

We had a water ingress issue into the tube on my Fathers first Flatacraft Force4.

We suddenly realised one day off Beesands in Devon that the Starboard tube had started to increase in pressure slightly, but then rapidly escalated to the point where we were worried about the tube splitting a seam.

We got the boat up on the beach and found the wide tape over the seam where the end cone joined the main tube hanging off, then whilst prodding around the joint underneath the tape we got a squirt of water from it.

The pressure of the water on the seam as it was dragged through the water at speed was forcing water through a very small gap in the seam, but then the pressure inside the tube was closing the gap at rest.

The tube held air perfectly until the seam was pressed out of shape.

It was a really difficult repair on the beach that evening as we had to open the seam up and get the water out after we'd deflated the tube enough.
The boat was significantly heavier on that side, and an unbelievable amount of water came out.

[willk]

IMO big fix the seam and small fix the cone first. Once leak is proven fixed, big fix the cone. I would drill a small diameter hole in the underside of the cone, ideally at the lowest point of the pooling water. Temp seal with a bit of tape or putty like product. Once leaking stops, use gelcoat filler to effect a permenant invisible repair.

[User name]

There's a baffle in behind this step, so the water may well be sitting between the fibreglass and the baffle. I'd be very careful about drilling a drain in there and you'd need to be confident that no sharp debris has fallen inside that might cause damage.

[willk]

Originally Posted by User name

and you'd need to be confident that no sharp debris has fallen inside that might cause damage.

Good point! ^

[Nasher]

Originally Posted by User name

There's a baffle in behind this step, so the water may well be sitting between the fibreglass and the baffle.

That makes a lot of sense, so it's a conventional tube rather than using the moulding as an end.

In that case I'd be very tempted to try to peel off the fake teak decking, then carefully cut a hole in the moulding below it to see what's going on.
The water can be sucked out with a small tube.
My guess is that rather like my Flatacraft explanation above the water is being forced in under a finishing tape as the end of the tube drags at speed.

At least by cutting a hole under the fake teak decking it will be covered when it's stuck back down.

[markpj23]

Originally Posted by Nasher

That makes a lot of sense, so it's a conventional tube rather than using the moulding as an end.

In that case I'd be very tempted to try to peel off the fake teak decking, then carefully cut a hole in the moulding below it to see what's going on.
The water can be sucked out with a small tube.
My guess is that rather like my Flatacraft explanation above the water is being forced in under a finishing tape as the end of the tube drags at speed.

At least by cutting a hole under the fake teak decking it will be covered when it's stuck back down.

I agree - the seam that appears to hold the end cap on has a small section that's starting to peel back. At speed it will surely act as a scoop.


I like the idea of peeling back the fake teak and going in from there.


What should I use to re-seal the seam? Can I just add some glue to what's already there?

[Peter_C]

If it has a baffle using a vacuum cleaner over the valve should suck it in if there is a leak. Might be able to find the leak that way before disassembling anything. Get a spray bottle with detergent and water for creating bubbles. Suck the tube down for awhile, then quickly fill the tube back up with an air compressor while someone looks and sprays down the end cone. The leak should be revealed by bubbles. Removing the valve and using a camera/bore scope should tell the story of how it is designed.

Nasher comes up with the one in a million trick "Anything is possible".

[markpj23]

Thanks for all the replies. I'll let you know what I find over the next few days.